Enable strict memory safety

Package.swift

@@ -52,6 +52,8 @@ var targetDependencies = [PackageDescription.Target.Dependency]()
 var settings: [SwiftSetting]? = [
     // Add build settings here
     .enableExperimentalFeature("Lifetimes"),
+    .strictMemorySafety(),
+    .treatWarning("StrictMemorySafety", as: .error),
 ]
 
 #if os(Linux)

Sources/ArraySpanUtilities.swift

@@ -19,9 +19,9 @@ extension Array where Element == UInt8 {
     ///
     /// The span must contain exactly `count` bytes.
     init(copying bytes: RawSpan) {
-        self.init(unsafeUninitializedCapacity: bytes.byteCount) { outputBuffer, initializedCount in
+        unsafe self.init(unsafeUninitializedCapacity: bytes.byteCount) { outputBuffer, initializedCount in
             bytes.withUnsafeBytes { inputBuffer in
-                UnsafeMutableRawBufferPointer(outputBuffer).copyMemory(from: inputBuffer)
+                unsafe UnsafeMutableRawBufferPointer(outputBuffer).copyMemory(from: inputBuffer)
             }
             initializedCount = bytes.byteCount
         }
@@ -38,7 +38,7 @@ extension InlineArray where Element == UInt8 {
         precondition(count == bytes.byteCount)
         self.init { outputSpan in
             for i in 0..<count {
-                outputSpan.append(bytes.unsafeLoad(fromByteOffset: i, as: UInt8.self))
+                outputSpan.append(unsafe bytes.unsafeLoad(fromByteOffset: i, as: UInt8.self))
             }
         }
     }
@@ -49,7 +49,7 @@ extension InlineArray where Element == UInt8 {
 extension Hasher {
     mutating func combine(bytes: RawSpan) {
         bytes.withUnsafeBytes { buffer in
-            self.combine(bytes: buffer)
+            unsafe self.combine(bytes: buffer)
         }
     }
 }
@@ -74,7 +74,7 @@ extension OutputRawSpan {
     /// Appends the contents of the given raw span to this output span.
     mutating func append(contentsOf bytes: RawSpan) {
         for i in 0..<bytes.byteCount {
-            append(bytes.unsafeLoad(fromByteOffset: i, as: UInt8.self))
+            append(unsafe bytes.unsafeLoad(fromByteOffset: i, as: UInt8.self))
         }
     }
 }
@@ -83,6 +83,6 @@ extension OutputRawSpan {
 @available(SwiftTLS 0.1.0, *)
 extension RawSpan {
     subscript(index: Int) -> UInt8 {
-        unsafeLoad(fromByteOffset: index, as: UInt8.self)
+        unsafe unsafeLoad(fromByteOffset: index, as: UInt8.self)
     }
 }

Sources/ByteBuffer.swift

@@ -90,7 +90,7 @@ struct ByteBuffer {
         var networkByteOrder = integer.bigEndian
         withUnsafeBytes(of: &networkByteOrder) {
             precondition($0.count == byteWidth)
-            self.backingData.append(contentsOf: $0)
+            unsafe self.backingData.append(contentsOf: $0)
         }
 
         return byteWidth
@@ -108,7 +108,7 @@ struct ByteBuffer {
         var networkByteOrder = integer.bigEndian
         withUnsafeBytes(of: &networkByteOrder) {
             precondition($0.count == byteWidth)
-            self.backingData.replaceSubrange(index..<endIndex, with: $0)
+            unsafe self.backingData.replaceSubrange(index..<endIndex, with: $0)
         }
 
         return byteWidth
@@ -128,10 +128,10 @@ struct ByteBuffer {
 
         _ = withUnsafeMutableBytes(of: &value) {
             #if canImport(Foundation) && !SWIFTTLS_EMBEDDED
-            self.backingData.copyBytes(to: $0, from: self.readerIndex..<endIndex)
+            unsafe self.backingData.copyBytes(to: $0, from: self.readerIndex..<endIndex)
             #else
             // SwiftSystem Data is missing copyBytes(to: from:)
-            $0.copyBytes(from: self.backingData[self.readerIndex..<endIndex])
+            unsafe $0.copyBytes(from: self.backingData[self.readerIndex..<endIndex])
             #endif
         }
         return IntegerType(bigEndian: value)

Sources/Cryptography/HKDF+Label.swift

@@ -18,7 +18,7 @@ import Foundation
 #if canImport(CryptoKit)
 import CryptoKit
 #elseif canImport(Crypto)
-@preconcurrency import Crypto
+@preconcurrency @unsafe import Crypto
 #endif
 
 // Availability due to `CryptoKit`'s `HKDF`
@@ -48,9 +48,9 @@ extension HKDF {
         serializedLabel.append(contentsOf: "tls13 ".utf8)
         serializedLabel.append(contentsOf: label.utf8)
 
-        context.withUnsafeBytes { contextPointer in
+        unsafe context.withUnsafeBytes { contextPointer in
             serializedLabel.append(UInt8(contextPointer.count))
-            serializedLabel.append(contentsOf: contextPointer)
+            unsafe serializedLabel.append(contentsOf: contextPointer)
         }
 
         return Self.expand(pseudoRandomKey: secret, info: serializedLabel, outputByteCount: length)
@@ -67,11 +67,11 @@ extension HKDF {
 
     static func extract(inputKeyMaterial ikm: SymmetricKey, salt: SymmetricKey) -> HashedAuthenticationCode<H> {
         // This wrapper helps us deal with the fact that these types don't neatly fit into what CryptoKit wants.
-        return salt.withUnsafeBytes { saltPointer in
+        return unsafe salt.withUnsafeBytes { saltPointer in
             #if SWIFTTLS_EXCLAVEKIT
-            Self.extract(inputKeyMaterial: ikm, salt: Data(saltPointer))
+            unsafe Self.extract(inputKeyMaterial: ikm, salt: Data(saltPointer))
             #else
-            Self.extract(inputKeyMaterial: ikm, salt: saltPointer)
+            unsafe Self.extract(inputKeyMaterial: ikm, salt: saltPointer)
             #endif
         }
     }

Sources/Cryptography/HashFunction+Helpers.swift

@@ -18,7 +18,7 @@ import Foundation
 #if canImport(CryptoKit)
 import CryptoKit
 #elseif canImport(Crypto)
-@preconcurrency import Crypto
+@preconcurrency @unsafe import Crypto
 #endif
 
 // Availability due to `CryptoKit`'s `HashFunction`
@@ -33,8 +33,8 @@ extension HashFunction {
 @available(macOS 10.15, iOS 13, tvOS 13, watchOS 6, *)
 extension HMAC {
     static func authenticationCode<Bytes: ContiguousBytes>(bytes: Bytes, using key: SymmetricKey) -> HashedAuthenticationCode<H> {
-        return bytes.withUnsafeBytes {
-            Self.authenticationCode(for: $0, using: key)
+        return unsafe bytes.withUnsafeBytes {
+            unsafe Self.authenticationCode(for: $0, using: key)
         }
     }
 }

Sources/Cryptography/KeyScheduler.swift

@@ -18,7 +18,7 @@ import Foundation
 #if canImport(CryptoKit)
 import CryptoKit
 #elseif canImport(Crypto)
-@preconcurrency import Crypto
+@preconcurrency @unsafe import Crypto
 #endif
 #if canImport(Darwin) || SWIFTTLS_EXCLAVEKIT
 import os.log
@@ -518,7 +518,7 @@ fileprivate struct SessionKeyManager<HF: HashFunction> {
         var transcriptHasher = HF()
         transcriptHasher.update(data: transcript.readableBytesView)
         let hash = transcriptHasher.finalize()
-        hash.withUnsafeBytes { _ = buffer.writeBytes($0) }
+        unsafe hash.withUnsafeBytes { _ = unsafe buffer.writeBytes($0) }
         return buffer
     }
 
@@ -893,7 +893,7 @@ extension SessionKeyManager.State {
             buffer.writeInteger(UInt8(0))
 
             let hash = self.transcriptHasher.finalize()
-            hash.withUnsafeBytes { _ = buffer.writeBytes($0) }
+            unsafe hash.withUnsafeBytes { _ = unsafe buffer.writeBytes($0) }
             return buffer
         }
     }
@@ -956,7 +956,7 @@ extension SessionKeyManager.State {
             buffer.writeInteger(UInt8(0))
 
             let hash = self.transcriptHasher.finalize()
-            hash.withUnsafeBytes { _ = buffer.writeBytes($0) }
+            unsafe hash.withUnsafeBytes { _ = unsafe buffer.writeBytes($0) }
             return buffer
         }
 

Sources/Cryptography/PrivateKey.swift

@@ -18,7 +18,7 @@ import Foundation
 #if canImport(CryptoKit)
 import CryptoKit
 #elseif canImport(Crypto)
-@preconcurrency import Crypto
+@preconcurrency @unsafe import Crypto
 #endif
 
 /// A generic wrapper over the supported private-key types.

Sources/Cryptography/PublicKey.swift

@@ -18,7 +18,7 @@ import Foundation
 #if canImport(CryptoKit)
 import CryptoKit
 #elseif canImport(Crypto)
-@preconcurrency import Crypto
+@preconcurrency @unsafe import Crypto
 #endif
 
 /// An opaque wrapper around the supported public-key types.

Sources/DataUtilities.swift

@@ -25,7 +25,7 @@ extension Data {
             self = Data()
         } else {
             self = bytes.withUnsafeBytes { buffer in
-                Data(
+                unsafe Data(
                     UnsafeBufferPointer<UInt8>(
                         start: buffer.baseAddress!.assumingMemoryBound(to: UInt8.self),
                         count: buffer.count
@@ -38,17 +38,17 @@ extension Data {
     /// Appends the contents of the given span to this `Data` instance.
     mutating func append(contentsOf bytes: RawSpan) {
         bytes.withUnsafeBytes { buffer in
-            self.append(contentsOf: buffer)
+            unsafe self.append(contentsOf: buffer)
         }
     }
 
     /// Calls `body` with a `RawSpan` describing the bytes.
     ///
     /// Used as a workaround for SwiftSystem's `Data` missing the `bytes` property.
     func withBytes<R, E: Error>(_ body: (RawSpan) throws(E) -> R) throws(E) -> R {
-        let result: Result<R, E> = self.withUnsafeBytes { bufferPointer in
+        let result: Result<R, E> = unsafe self.withUnsafeBytes { bufferPointer in
             do throws(E) {
-                return .success(try body(bufferPointer.bytes))
+                return .success(try body(unsafe bufferPointer.bytes))
             } catch {
                 return .failure(error)
             }
@@ -62,33 +62,34 @@ extension Data {
 //
 // Use this wrapper to turn an UnsafeRawBufferPointer into something that conforms to
 // DataProtocol. This whole type should go away once the issue is fixed.
-struct UnsafeRawBufferPointerWrapper: DataProtocol, RandomAccessCollection, ContiguousBytes {
+@unsafe
+struct UnsafeRawBufferPointerWrapper: @unsafe DataProtocol, @unsafe RandomAccessCollection, ContiguousBytes {
     var wrapped: UnsafeRawBufferPointer
 
     typealias Element = UInt8
     typealias Index = Int
     typealias Regions = CollectionOfOne<UnsafeRawBufferPointerWrapper>
 
     var regions: CollectionOfOne<UnsafeRawBufferPointerWrapper> {
-        CollectionOfOne(self)
+        unsafe CollectionOfOne(self)
     }
 
-    var startIndex: Int { wrapped.startIndex }
-    var endIndex: Int { wrapped.endIndex }
+    var startIndex: Int { unsafe wrapped.startIndex }
+    var endIndex: Int { unsafe wrapped.endIndex }
 
     subscript(index: Int) -> UInt8 {
         get {
-            wrapped[index]
+            unsafe wrapped[index]
         }
     }
 
     #if $Embedded
     func withUnsafeBytes<R, E>(_ body: (UnsafeRawBufferPointer) throws(E) -> R) throws(E) -> R {
-        try wrapped.withUnsafeBytes(body)
+        try unsafe wrapped.withUnsafeBytes(body)
     }
     #else
     func withUnsafeBytes<R>(_ body: (UnsafeRawBufferPointer) throws -> R) rethrows -> R {
-        try wrapped.withUnsafeBytes(body)
+        try unsafe wrapped.withUnsafeBytes(body)
     }
     #endif
 }

Sources/Handshake/ExternalPreSharedKey.swift

@@ -18,7 +18,7 @@ import Foundation
 #if canImport(CryptoKit)
 import CryptoKit
 #elseif canImport(Crypto)
-@preconcurrency import Crypto
+@preconcurrency @unsafe import Crypto
 #endif
 
 // Availability due to `RawSpan`

Sources/Handshake/HandshakeState.swift

@@ -18,7 +18,7 @@ import Foundation
 #if canImport(CryptoKit)
 import CryptoKit
 #elseif canImport(Crypto)
-@preconcurrency import Crypto
+@preconcurrency @unsafe import Crypto
 #endif
 
 #if canImport(Darwin) || SWIFTTLS_EXCLAVEKIT

Sources/Handshake/HandshakeStateMachine.swift

@@ -18,7 +18,7 @@ import Foundation
 #if canImport(CryptoKit)
 import CryptoKit
 #elseif canImport(Crypto)
-@preconcurrency import Crypto
+@preconcurrency @unsafe import Crypto
 #endif
 
 #if canImport(Darwin) || SWIFTTLS_EXCLAVEKIT

Sources/Handshake/HandshakeStateMachineConfiguration.swift

@@ -18,7 +18,7 @@ import Foundation
 #if canImport(CryptoKit)
 import CryptoKit
 #elseif canImport(Crypto)
-@preconcurrency import Crypto
+@preconcurrency @unsafe import Crypto
 #endif
 
 #if canImport(Darwin) || SWIFTTLS_EXCLAVEKIT

Sources/Handshake/PartialHandshakeResult.swift

@@ -18,7 +18,7 @@ import Foundation
 #if canImport(CryptoKit)
 import CryptoKit
 #elseif canImport(Crypto)
-@preconcurrency import Crypto
+@preconcurrency @unsafe import Crypto
 #endif
 
 // Availability due to `RawSpan`

Sources/Handshake/PeerCertificateBundle.swift

@@ -18,7 +18,7 @@ import Foundation
 #if canImport(CryptoKit)
 import CryptoKit
 #elseif canImport(Crypto)
-@preconcurrency import Crypto
+@preconcurrency @unsafe import Crypto
 #endif
 
 #if canImport(Darwin) || SWIFTTLS_EXCLAVEKIT
@@ -308,7 +308,7 @@ extension InputBuffer {
         case 0:
             let key = try TLSError.wrappingCryptoError { () throws(CryptoKitMetaError) in try self.readLengthPrefixed { buffer throws(CryptoKitMetaError) in
                 try buffer.bytes.withUnsafeBytes { (bytes) throws(CryptoKitMetaError) in
-                    try P256.Signing.PublicKey(rawRepresentation: bytes)
+                    try unsafe P256.Signing.PublicKey(rawRepresentation: bytes)
                 }
             } }
             guard let key = key else {

Sources/Handshake/ServerHandshakeState.swift

@@ -18,7 +18,7 @@ import Foundation
 #if canImport(CryptoKit)
 import CryptoKit
 #elseif canImport(Crypto)
-@preconcurrency import Crypto
+@preconcurrency @unsafe import Crypto
 #endif
 
 #if !SWIFTTLS_CLIENT_ONLY

Sources/Handshake/ServerHandshakeStateMachine.swift

@@ -18,7 +18,7 @@ import Foundation
 #if canImport(CryptoKit)
 import CryptoKit
 #elseif canImport(Crypto)
-@preconcurrency import Crypto
+@preconcurrency @unsafe import Crypto
 #endif
 
 #if !SWIFTTLS_CLIENT_ONLY

Sources/Handshake/ServerHandshakeStateMachineConfiguration.swift

@@ -15,7 +15,7 @@
 #if canImport(CryptoKit)
 import CryptoKit
 #elseif canImport(Crypto)
-@preconcurrency import Crypto
+@preconcurrency @unsafe import Crypto
 #endif
 
 #if canImport(Foundation) && !SWIFTTLS_EMBEDDED

Sources/Handshake/SessionTicket.swift

@@ -18,7 +18,7 @@ import Foundation
 #if canImport(CryptoKit)
 import CryptoKit
 #elseif canImport(Crypto)
-@preconcurrency import Crypto
+@preconcurrency @unsafe import Crypto
 #endif
 
 #if canImport(Darwin) || SWIFTTLS_EXCLAVEKIT
@@ -126,8 +126,8 @@ struct SessionTicket {
         buffer.writeLengthPrefixedImmutableBuffer(self.nonce)
         buffer.writeLengthPrefixedImmutableBuffer(self.ticket)
 
-        self.psk.withUnsafeBytes {
-            buffer.writeLengthPrefixedBytes($0)
+        unsafe self.psk.withUnsafeBytes {
+            unsafe buffer.writeLengthPrefixedBytes($0)
         }
 
         buffer.writeInteger(self.maxEarlyDataSize)

Sources/InputBuffer.swift

@@ -100,14 +100,14 @@ extension InputBuffer {
         // Copy those bytes into a temporary value.
         let align = MemoryLayout<Value>.alignment
         return withUnsafeTemporaryAllocation(byteCount: byteCount, alignment: align) { valueBuffer in
-            var outputSpan = OutputRawSpan(
+            var outputSpan = unsafe OutputRawSpan(
                 buffer: valueBuffer,
                 initializedCount: 0
             )
             bytes.copy(to: &outputSpan)
-            let bytesWritten = outputSpan.finalize(for: valueBuffer)
+            let bytesWritten = unsafe outputSpan.finalize(for: valueBuffer)
             precondition(bytesWritten == byteCount)
-            return valueBuffer.load(as: Value.self)
+            return unsafe valueBuffer.load(as: Value.self)
         }
     }